From the Super Mario Wiki
Mario Kart series
Mario Kart: Double Dash!!
Like Diddy Kong's Barrel Train, the Bullet Blaster is one of the fastest lightweight karts in the game. It is also the lightest kart in the game, and can be knocked around by any other kart of any weight class. Another one of the kart's good stats is its acceleration, which is lower than the regular lightweight kart, but still better than a heavyweight. Its horn makes the sound of a noisemaker. The Bullet Blaster is unlocked by completing the Special Cup in 50cc.
In terms of its actual stats, while the Bullet Blaster does have a three star acceleration stat, it is one of the weaker accelerating karts, equalling the Red Fire, Turbo Birdo, and Parade Kart. Also, its top speed, with four stars, is tied with that of the Barrel Train, DK Jumbo, and Piranha Pipes. Lastly, although the Bullet Blaster is a lightweight kart, with a one-star weight, it is tied with the Koopa King for having the slowest off-road speed in the game.
Mario Kart Tour
The Bullet Blaster returns in Mario Kart Tour, where it appears as a Normal kart. Its design has been updated to be more in line with the Banzai Bill's appearances post-New Super Mario Bros., but with the same yellow rotor as in Double Dash!!. It uses the Roller tires from Mario Kart 7. Rocket Starts are more powerful and yield more points while using this kart. The game also introduces a red variant, named the Bull's-Eye Banzai, which also has the Normal classification.
Super Smash Bros. Brawl
Super Smash Bros. Brawl sticker
Mario Kart Tour
Names in other languages